I've enabled the queue.drain: true setting on one of my logstash instances which has a persistent queue. The behavior I would expect is that when I stop the logstash process (service logstash stop) the page files would be drained, processed and flushed. Instead what I see is a pagefile that seems to have data in it (wc shows several thousand lines), and when I tail the file there is what appears to be serialized input data.

Is this the expected behavior for queue.drain, or am I missing something?